#!/usr/bin/env python3
# coding: utf-8

import asyncore
import click
import configparser
import hashlib
import logging
import os
import pwd
import re
import signal
import socket
import subprocess
import sys
from certidude.signer import SignServer
from certidude.common import expand_paths
from datetime import datetime
from humanize import naturaltime
from ipaddress import ip_network, ip_address
from jinja2 import Environment, PackageLoader
from time import sleep
from setproctitle import setproctitle
from OpenSSL import crypto

env = Environment(loader=PackageLoader("certidude", "templates"), trim_blocks=True)

# Big fat warning:
# m2crypto overflows around 2030 because on 32-bit systems
# m2crypto does not support hardware engine support (?)
# m2crypto CRL object is pretty much useless

# pyopenssl has no straight-forward methods for getting RSA key modulus

# pyopenssl 0.13 bundled with Ubuntu 14.04 has no get_extension_count() for X509Req objects
assert hasattr(crypto.X509Req(), "get_extensions"), "You're running too old version of pyopenssl, upgrade to 0.15+"

# http://www.mad-hacking.net/documentation/linux/security/ssl-tls/creating-ca.xml
# https://kjur.github.io/jsrsasign/
# keyUsage, extendedKeyUsage - https://www.openssl.org/docs/apps/x509v3_config.html
# strongSwan key paths - https://wiki.strongswan.org/projects/1/wiki/SimpleCA

# Parse command-line argument defaults from environment
HOSTNAME = socket.gethostname()
FQDN = socket.getaddrinfo(HOSTNAME, 0, flags=socket.AI_CANONNAME)[0][3]
USERNAME = os.environ.get("USER")
NOW = datetime.utcnow().replace(tzinfo=None)
FIRST_NAME = None
SURNAME = None
EMAIL = None

if USERNAME:
    EMAIL = USERNAME + "@" + FQDN

if os.getuid() >= 1000:
    _, _, _, _, gecos, _, _ = pwd.getpwnam(USERNAME)
    if " " in gecos:
        FIRST_NAME, SURNAME = gecos.split(" ", 1)
    else:
        FIRST_NAME = gecos


@click.command("spawn", help="Run privilege isolated signer process")
@click.option("-k", "--kill", default=False, is_flag=True, help="Kill previous instance")
@click.option("-n", "--no-interaction", default=True, is_flag=True, help="Don't load password protected keys")
def certidude_spawn(kill, no_interaction):
    """
    Spawn processes for signers
    """
    from certidude import config

    # Check whether we have privileges
    os.umask(0o027)
    uid = os.getuid()
    if uid != 0:
        raise click.ClickException("Not running as root")

    # Process directories
    run_dir = "/run/certidude"
    chroot_dir = os.path.join(run_dir, "jail")

    # Prepare signer PID-s directory
    if not os.path.exists(run_dir):
        click.echo("Creating: %s" % run_dir)
        os.makedirs(run_dir)

    # Preload charmap encoding for byte_string() function of pyOpenSSL
    # in order to enable chrooting
    "".encode("charmap")

    # Prepare chroot directories
    if not os.path.exists(os.path.join(chroot_dir, "dev")):
        os.makedirs(os.path.join(chroot_dir, "dev"))
    if not os.path.exists(os.path.join(chroot_dir, "dev", "urandom")):
        # TODO: use os.mknod instead
        os.system("mknod -m 444 %s c 1 9" % os.path.join(chroot_dir, "dev", "urandom"))

    ca_loaded = False


    try:
        with open(config.SIGNER_PID_PATH) as fh:
            pid = int(fh.readline())
            os.kill(pid, 0)
            click.echo("Found process with PID %d" % pid)
    except (ValueError, ProcessLookupError, FileNotFoundError):
        pid = 0

    if pid > 0:
        if kill:
            try:
                click.echo("Killing %d" % pid)
                os.kill(pid, signal.SIGTERM)
                sleep(1)
                os.kill(pid, signal.SIGKILL)
                sleep(1)
            except ProcessLookupError:
                pass

    child_pid = os.fork()

    if child_pid == 0:
        with open(config.SIGNER_PID_PATH, "w") as fh:
            fh.write("%d\n" % os.getpid())

#        setproctitle("%s spawn %s" % (sys.argv[0], ca.common_name))
        logging.basicConfig(
            filename="/var/log/signer.log",
            level=logging.INFO)
        server = SignServer(
            config.SIGNER_SOCKET_PATH,
            config.AUTHORITY_PRIVATE_KEY_PATH,
            config.AUTHORITY_CERTIFICATE_PATH,
            config.CERTIFICATE_LIFETIME,
            config.CERTIFICATE_BASIC_CONSTRAINTS,
            config.CERTIFICATE_KEY_USAGE_FLAGS,
            config.CERTIFICATE_EXTENDED_KEY_USAGE_FLAGS,
            config.REVOCATION_LIST_LIFETIME)
        asyncore.loop()
    else:
        click.echo("Spawned certidude signer process with PID %d at %s" % (child_pid, config.SIGNER_SOCKET_PATH))


@click.command("client", help="Setup X.509 certificates for application")
@click.argument("url") #, help="Certidude authority endpoint URL")
@click.option("--common-name", "-cn", default=HOSTNAME, help="Common name, '%s' by default" % HOSTNAME)
@click.option("--org-unit", "-ou", help="Organizational unit")
@click.option("--email-address", "-m", default=EMAIL, help="E-mail associated with the request, '%s' by default" % EMAIL)
@click.option("--given-name", "-gn", default=FIRST_NAME, help="Given name of the person associted with the certificate, '%s' by default" % FIRST_NAME)
@click.option("--surname", "-sn", default=SURNAME, help="Surname of the person associted with the certificate, '%s' by default" % SURNAME)
@click.option("--key-usage", "-ku", help="Key usage attributes, none requested by default")
@click.option("--extended-key-usage", "-eku", help="Extended key usage attributes, none requested by default")
@click.option("--quiet", "-q", default=False, is_flag=True, help="Disable verbose output")
@click.option("--autosign", "-s", default=False, is_flag=True, help="Request for automatic signing if available")
@click.option("--wait", "-w", default=False, is_flag=True, help="Wait for certificate, by default return immideately")
@click.option("--key-path", "-k", default=HOSTNAME + ".key", help="Key path, %s.key by default" % HOSTNAME)
@click.option("--request-path", "-r", default=HOSTNAME + ".csr", help="Request path, %s.csr by default" % HOSTNAME)
@click.option("--certificate-path", "-c", default=HOSTNAME + ".crt", help="Certificate path, %s.crt by default" % HOSTNAME)
@click.option("--authority-path", "-a", default="ca.crt", help="Certificate authority certificate path, ca.crt by default")
def certidude_setup_client(quiet, **kwargs):
    from certidude.helpers import certidude_request_certificate
    return certidude_request_certificate(**kwargs)


@click.command("server", help="Set up OpenVPN server")
@click.argument("url")
@click.option("--common-name", "-cn", default=FQDN, help="Common name, %s by default" % FQDN)
@click.option("--org-unit", "-ou", help="Organizational unit")
@click.option("--email-address", "-m", default=EMAIL, help="E-mail associated with the request, '%s' by default" % EMAIL)
@click.option("--subnet", "-s", default="192.168.33.0/24", type=ip_network, help="OpenVPN subnet, 192.168.33.0/24 by default")
@click.option("--local", "-l", default="127.0.0.1", help="OpenVPN listening address, defaults to 127.0.0.1")
@click.option("--port", "-p", default=1194, type=click.IntRange(1,60000), help="OpenVPN listening port, 1194 by default")
@click.option('--proto', "-t", default="udp", type=click.Choice(['udp', 'tcp']), help="OpenVPN transport protocol, UDP by default")
@click.option("--route", "-r", type=ip_network, multiple=True, help="Subnets to advertise via this connection, multiple allowed")
@click.option("--config", "-o",
    default="/etc/openvpn/site-to-client.conf",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="OpenVPN configuration file")
@click.option("--directory", "-d", default="/etc/openvpn/keys", help="Directory for keys, /etc/openvpn/keys by default")
@click.option("--key-path", "-key", default=HOSTNAME + ".key", help="Key path, %s.key relative to --directory by default" % HOSTNAME)
@click.option("--request-path", "-csr", default=HOSTNAME + ".csr", help="Request path, %s.csr relative to --directory by default" % HOSTNAME)
@click.option("--certificate-path", "-crt", default=HOSTNAME + ".crt", help="Certificate path, %s.crt relative to --directory by default" % HOSTNAME)
@click.option("--dhparam-path", "-dh", default="dhparam2048.pem", help="Diffie/Hellman parameters path, dhparam2048.pem relative to --directory by default")
@click.option("--authority-path", "-ca", default="ca.crt", help="Certificate authority certificate path, ca.crt relative to --dir by default")
@expand_paths()
def certidude_setup_openvpn_server(url, config, subnet, route, email_address, common_name, org_unit, directory, key_path, request_path, certificate_path, authority_path, dhparam_path, local, proto, port):
    # TODO: Intelligent way of getting last IP address in the subnet
    from certidude.helpers import certidude_request_certificate
    subnet_first = None
    subnet_last = None
    subnet_second = None
    for addr in subnet.hosts():
        if not subnet_first:
            subnet_first = addr
            continue
        if not subnet_second:
            subnet_second = addr
        subnet_last = addr

    if not os.path.exists(certificate_path):
        click.echo("As OpenVPN server certificate needs specific key usage extensions please")
        click.echo("use following command to sign on Certidude server instead of web interface:")
        click.echo()
        click.echo("  certidude sign %s" % common_name)
    retval = certidude_request_certificate(
        url,
        key_path,
        request_path,
        certificate_path,
        authority_path,
        common_name,
        org_unit,
        email_address,
        key_usage="nonRepudiation,digitalSignature,keyEncipherment",
        extended_key_usage="serverAuth,ikeIntermediate",
        wait=True)

    if not os.path.exists(dhparam_path):
        cmd = "openssl", "dhparam", "-out", dhparam_path, "2048"
        subprocess.check_call(cmd)

    if retval:
        return retval

    # TODO: Add dhparam
    config.write(env.get_template("openvpn-site-to-client.ovpn").render(locals()))

    click.echo("Generated %s" % config.name)
    click.echo()
    click.echo("Inspect newly created %s and start OpenVPN service:" % config.name)
    click.echo()
    click.secho("  service openvpn restart", bold=True)
    click.echo()


@click.command("client", help="Set up OpenVPN client")
@click.argument("url")
@click.argument("remote")
@click.option('--proto', "-t", default="udp", type=click.Choice(['udp', 'tcp']), help="OpenVPN transport protocol, UDP by default")
@click.option("--common-name", "-cn", default=HOSTNAME, help="Common name, %s by default" % HOSTNAME)
@click.option("--org-unit", "-ou", help="Organizational unit")
@click.option("--email-address", "-m", default=EMAIL, help="E-mail associated with the request, '%s' by default" % EMAIL)
@click.option("--config", "-o",
    default="/etc/openvpn/client-to-site.conf",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="OpenVPN configuration file")
@click.option("--directory", "-d", default="/etc/openvpn/keys", help="Directory for keys, /etc/openvpn/keys by default")
@click.option("--key-path", "-k", default=HOSTNAME + ".key", help="Key path, %s.key relative to --directory by default" % HOSTNAME)
@click.option("--request-path", "-r", default=HOSTNAME + ".csr", help="Request path, %s.csr relative to --directory by default" % HOSTNAME)
@click.option("--certificate-path", "-c", default=HOSTNAME + ".crt", help="Certificate path, %s.crt relative to --directory by default" % HOSTNAME)
@click.option("--authority-path", "-a", default="ca.crt", help="Certificate authority certificate path, ca.crt relative to --dir by default")
@expand_paths()
def certidude_setup_openvpn_client(url, config, email_address, common_name, org_unit, directory, key_path, request_path, certificate_path, authority_path, proto, remote):
    from certidude.helpers import certidude_request_certificate
    retval = certidude_request_certificate(
        url,
        key_path,
        request_path,
        certificate_path,
        authority_path,
        common_name,
        org_unit,
        email_address,
        wait=True)

    if retval:
        return retval

    # TODO: Add dhparam
    config.write(env.get_template("openvpn-client-to-site.ovpn").render(locals()))

    click.echo("Generated %s" % config.name)
    click.echo()
    click.echo("Inspect newly created %s and start OpenVPN service:" % config.name)
    click.echo()
    click.echo("  service openvpn restart")
    click.echo()


@click.command("server", help="Set up strongSwan server")
@click.argument("url")
@click.option("--common-name", "-cn", default=FQDN, help="Common name, %s by default" % FQDN)
@click.option("--org-unit", "-ou", help="Organizational unit")
@click.option("--fqdn", "-f", default=FQDN, help="Fully qualified hostname associated with the certificate")
@click.option("--email-address", "-m", default=EMAIL, help="E-mail associated with the request, %s by default" % EMAIL)
@click.option("--subnet", "-s", default="192.168.33.0/24", type=ip_network, help="IPsec virtual subnet, 192.168.33.0/24 by default")
@click.option("--local", "-l", default=None, type=ip_address, help="IP address associated with the certificate, none by default")
@click.option("--route", "-r", type=ip_network, multiple=True, help="Subnets to advertise via this connection, multiple allowed")
@click.option("--config", "-o",
    default="/etc/ipsec.conf",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="strongSwan configuration file, /etc/ipsec.conf by default")
@click.option("--secrets", "-s",
    default="/etc/ipsec.secrets",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="strongSwan secrets file, /etc/ipsec.secrets by default")
@click.option("--directory", "-d", default="/etc/ipsec.d", help="Directory for keys, /etc/ipsec.d by default")
@click.option("--key-path", "-key", default="private/%s.pem" % HOSTNAME, help="Key path, private/%s.pem by default" % HOSTNAME)
@click.option("--request-path", "-csr", default="reqs/%s.pem" % HOSTNAME, help="Request path, reqs/%s.pem by default" % HOSTNAME)
@click.option("--certificate-path", "-crt", default="certs/%s.pem" % HOSTNAME, help="Certificate path, certs/%s.pem by default" % HOSTNAME)
@click.option("--authority-path", "-ca", default="cacerts/ca.pem", help="Certificate authority certificate path, cacerts/ca.pem by default")
@expand_paths()
def certidude_setup_strongswan_server(url, config, secrets, subnet, route, email_address, common_name, org_unit, directory, key_path, request_path, certificate_path, authority_path, local, fqdn):
    if "." not in common_name:
        raise ValueError("Hostname has to be fully qualified!")
    if not local:
        raise ValueError("Please specify local IP address")

    if not os.path.exists(certificate_path):
        click.echo("As strongSwan server certificate needs specific key usage extensions please")
        click.echo("use following command to sign on Certidude server instead of web interface:")
        click.echo()
        click.echo("  certidude sign %s" % common_name)
    from certidude.helpers import certidude_request_certificate
    retval = certidude_request_certificate(
        url,
        key_path,
        request_path,
        certificate_path,
        authority_path,
        common_name,
        org_unit,
        email_address,
        key_usage="nonRepudiation,digitalSignature,keyEncipherment",
        extended_key_usage="serverAuth,1.3.6.1.5.5.8.2.2",
        ip_address=local,
        dns=fqdn,
        wait=True)

    if retval:
        return retval

    config.write(env.get_template("strongswan-site-to-client.conf").render(locals()))
    secrets.write(": RSA %s\n" % key_path)

    click.echo("Generated %s and %s" % (config.name, secrets.name))
    click.echo()
    click.echo("Inspect newly created %s and start strongSwan service:" % config.name)
    click.echo()
    click.echo("  apt-get install strongswan strongswan-starter strongswan-ikev2")
    click.secho("  service strongswan restart", bold=True)
    click.echo()


@click.command("client", help="Set up strongSwan client")
@click.argument("url")
@click.argument("remote")
@click.option("--common-name", "-cn", default=HOSTNAME, help="Common name, %s by default" % HOSTNAME)
@click.option("--org-unit", "-ou", help="Organizational unit")
@click.option("--email-address", "-m", default=EMAIL, help="E-mail associated with the request, '%s' by default" % EMAIL)
@click.option("--config", "-o",
    default="/etc/ipsec.conf",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="strongSwan configuration file, /etc/ipsec.conf by default")
@click.option("--secrets", "-s",
    default="/etc/ipsec.secrets",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="strongSwan secrets file, /etc/ipsec.secrets by default")
@click.option("--dpdaction", "-d",
    default="restart",
    type=click.Choice(["none", "clear", "hold", "restart"]),
    help="Action upon dead peer detection; either none, clear, hold or restart")
@click.option("--auto", "-a",
    default="start",
    type=click.Choice(["ignore", "add", "route", "start"]),
    help="Operation at startup; either ignore, add, route or start")
@click.option("--directory", "-d", default="/etc/ipsec.d", help="Directory for keys, /etc/ipsec.d by default")
@click.option("--key-path", "-key", default="private/%s.pem" % HOSTNAME, help="Key path, private/%s.pem by default" % HOSTNAME)
@click.option("--request-path", "-csr", default="reqs/%s.pem" % HOSTNAME, help="Request path, reqs/%s.pem by default" % HOSTNAME)
@click.option("--certificate-path", "-crt", default="certs/%s.pem" % HOSTNAME, help="Certificate path, certs/%s.pem by default" % HOSTNAME)
@click.option("--authority-path", "-ca", default="cacerts/ca.pem", help="Certificate authority certificate path, cacerts/ca.pem by default")
@expand_paths()
def certidude_setup_strongswan_client(url, config, secrets, email_address, common_name, org_unit, directory, key_path, request_path, certificate_path, authority_path, remote, auto, dpdaction):
    from certidude.helpers import certidude_request_certificate
    retval = certidude_request_certificate(
        url,
        key_path,
        request_path,
        certificate_path,
        authority_path,
        common_name,
        org_unit,
        email_address,
        wait=True)

    if retval:
        return retval

    # TODO: Add dhparam
    config.write(env.get_template("strongswan-client-to-site.conf").render(locals()))
    secrets.write(": RSA %s\n" % key_path)

    click.echo("Generated %s and %s" % (config.name, secrets.name))
    click.echo()
    click.echo("Inspect newly created %s and start strongSwan service:" % config.name)
    click.echo()
    click.echo("  apt-get install strongswan strongswan-starter")
    click.echo("  service strongswan restart")
    click.echo()


@click.command("networkmanager", help="Set up strongSwan client via NetworkManager")
@click.argument("url")
@click.argument("remote")
@click.option("--common-name", "-cn", default=HOSTNAME, help="Common name, %s by default" % HOSTNAME)
@click.option("--org-unit", "-ou", help="Organizational unit")
@click.option("--email-address", "-m", default=EMAIL, help="E-mail associated with the request, '%s' by default" % EMAIL)
@click.option("--directory", "-d", default="/etc/ipsec.d", help="Directory for keys, /etc/ipsec.d by default")
@click.option("--key-path", "-key", default="private/%s.pem" % HOSTNAME, help="Key path, private/%s.pem by default" % HOSTNAME)
@click.option("--request-path", "-csr", default="reqs/%s.pem" % HOSTNAME, help="Request path, reqs/%s.pem by default" % HOSTNAME)
@click.option("--certificate-path", "-crt", default="certs/%s.pem" % HOSTNAME, help="Certificate path, certs/%s.pem by default" % HOSTNAME)
@click.option("--authority-path", "-ca", default="cacerts/ca.pem", help="Certificate authority certificate path, cacerts/ca.pem by default")
@expand_paths()
def certidude_setup_strongswan_networkmanager(url, email_address, common_name, org_unit, directory, key_path, request_path, certificate_path, authority_path, remote):
    from certidude.helpers import certidude_request_certificate
    retval = certidude_request_certificate(
        url,
        key_path,
        request_path,
        certificate_path,
        authority_path,
        common_name,
        org_unit,
        email_address,
        wait=True)

    if retval:
        return retval

    csummer = hashlib.sha1()
    csummer.update(remote.encode("ascii"))
    csum = csummer.hexdigest()
    uuid = csum[:8] + "-" + csum[8:12] + "-" + csum[12:16] + "-" + csum[16:20] + "-" + csum[20:32]

    config = configparser.ConfigParser()
    config.add_section("connection")
    config.add_section("vpn")
    config.add_section("ipv4")

    config.set("connection", "id", remote)
    config.set("connection", "uuid", uuid)
    config.set("connection", "type", "vpn")
    config.set("connection", "autoconnect", "true")

    config.set("vpn", "service-type", "org.freedesktop.NetworkManager.strongswan")
    config.set("vpn", "userkey", key_path)
    config.set("vpn", "usercert", certificate_path)
    config.set("vpn", "encap", "no")
    config.set("vpn", "address", remote)
    config.set("vpn", "virtual", "yes")
    config.set("vpn", "method", "key")
    config.set("vpn", "certificate", authority_path)
    config.set("vpn", "ipcomp", "no")

    config.set("ipv4", "method", "auto")

    # Prevent creation of files with liberal permissions
    os.umask(0o277)

    # Write keyfile
    with open(os.path.join("/etc/NetworkManager/system-connections", remote), "w") as configfile:
        config.write(configfile)

    # TODO: Avoid race condition here
    sleep(3)

    # Tell NetworkManager to bring up the VPN connection
    subprocess.call(("nmcli", "c", "up", "uuid", uuid))


@click.command("production", help="Set up nginx and uwsgi")
@click.option("--username", default="certidude", help="Service user account, created if necessary, 'certidude' by default")
@click.option("--hostname", default=HOSTNAME, help="nginx hostname, '%s' by default" % HOSTNAME)
@click.option("--static-path", default=os.path.join(os.path.dirname(__file__), "static"), help="Static files")
@click.option("--kerberos-keytab", default="/etc/certidude.keytab", help="Specify Kerberos keytab")
@click.option("--nginx-config", "-n",
    default="/etc/nginx/nginx.conf",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="nginx configuration, /etc/nginx/nginx.conf by default")
@click.option("--uwsgi-config", "-u",
    default="/etc/uwsgi/apps-available/certidude.ini",
    type=click.File(mode="w", atomic=True, lazy=True),
    help="uwsgi configuration, /etc/uwsgi/ by default")
def certidude_setup_production(username, hostname, push_server, nginx_config, uwsgi_config, static_path, kerberos_keytab):
    try:
        pwd.getpwnam(username)
        click.echo("Username '%s' already exists, excellent!" % username)
    except KeyError:
        cmd = "adduser", "--system",  "--no-create-home", "--group", username
        subprocess.check_call(cmd)

    if subprocess.call("net ads testjoin", shell=True):
        click.echo("Domain membership check failed, 'net ads testjoin' returned non-zero value", stderr=True)
        exit(255)

    if not os.path.exists(kerberos_keytab):
        subprocess.call("KRB5_KTNAME=FILE:" + kerberos_keytab + " net ads keytab add HTTP -P")
        click.echo("Created Kerberos keytab in '%s'" % kerberos_keytab)

    if not static_path.endswith("/"):
        static_path += "/"

    nginx_config.write(env.get_template("nginx.conf").render(locals()))
    click.echo("Generated: %s" % nginx_config.name)
    uwsgi_config.write(env.get_template("uwsgi.ini").render(locals()))
    click.echo("Generated: %s" % uwsgi_config.name)

    if os.path.exists("/etc/uwsgi/apps-enabled/certidude.ini"):
        os.unlink("/etc/uwsgi/apps-enabled/certidude.ini")
    os.symlink(uwsgi_config.name, "/etc/uwsgi/apps-enabled/certidude.ini")
    click.echo("Symlinked %s -> /etc/uwsgi/apps-enabled/certidude.ini" % uwsgi_config.name)

    if not push_server:
        click.echo("Remember to install nginx with wandenberg/nginx-push-stream-module!")


@click.command("authority", help="Set up Certificate Authority in a directory")
@click.option("--parent", "-p", help="Parent CA, none by default")
@click.option("--common-name", "-cn", default=FQDN, help="Common name, fully qualified hostname by default")
@click.option("--country", "-c", default=None, help="Country, none by default")
@click.option("--state", "-s", default=None, help="State or country, none by default")
@click.option("--locality", "-l", default=None, help="City or locality, none by default")
@click.option("--authority-lifetime", default=20*365, help="Authority certificate lifetime in days, 7300 days (20 years) by default")
@click.option("--certificate-lifetime", default=5*365, help="Certificate lifetime in days, 1825 days (5 years) by default")
@click.option("--revocation-list-lifetime", default=1, help="Revocation list lifetime in days, 1 day by default")
@click.option("--organization", "-o", default=None, help="Company or organization name")
@click.option("--organizational-unit", "-ou", default=None)
@click.option("--pkcs11", default=False, is_flag=True, help="Use PKCS#11 token instead of files")
@click.option("--crl-distribution-url", default=None, help="CRL distribution URL")
@click.option("--ocsp-responder-url", default=None, help="OCSP responder URL")
@click.option("--push-server", default="", help="Streaming nginx push server")
@click.option("--email-address", default="certidude@" + FQDN, help="E-mail address of the CA")
@click.option("--directory", default=os.path.join("/var/lib/certidude", FQDN), help="Directory for authority files, /var/lib/certidude/ by default")
def certidude_setup_authority(parent, country, state, locality, organization, organizational_unit, common_name, directory, certificate_lifetime, authority_lifetime, revocation_list_lifetime, pkcs11, crl_distribution_url, ocsp_responder_url, push_server, email_address):

    # Make sure common_name is valid
    if not re.match(r"^[\.\-_a-zA-Z0-9]+$", common_name):
        raise click.ClickException("CA name can contain only alphanumeric, '_' and '-' characters")

    if os.path.lexists(directory):
        raise click.ClickException("Output directory {} already exists.".format(directory))

    click.echo("CA configuration files are saved to: {}".format(directory))

    click.echo("Generating 4096-bit RSA key...")

    if pkcs11:
        raise NotImplementedError("Hardware token support not yet implemented!")
    else:
        key = crypto.PKey()
        key.generate_key(crypto.TYPE_RSA, 4096)

    if not crl_distribution_url:
        crl_distribution_url = "http://%s/api/revoked/" % common_name

    # File paths
    ca_key = os.path.join(directory, "ca_key.pem")
    ca_crt = os.path.join(directory, "ca_crt.pem")
    ca_crl = os.path.join(directory, "ca_crl.pem")
    crl_distribution_points = "URI:%s" % crl_distribution_url

    ca = crypto.X509()
    ca.set_version(2) # This corresponds to X.509v3
    ca.set_serial_number(1)
    ca.get_subject().CN = common_name

    if country:
        ca.get_subject().C = country
    if state:
        ca.get_subject().ST = state
    if locality:
        ca.get_subject().L = locality
    if organization:
        ca.get_subject().O = organization
    if organizational_unit:
        ca.get_subject().OU = organizational_unit

    ca.gmtime_adj_notBefore(0)
    ca.gmtime_adj_notAfter(authority_lifetime * 24 * 60 * 60)
    ca.set_issuer(ca.get_subject())
    ca.set_pubkey(key)
    ca.add_extensions([
        crypto.X509Extension(
            b"basicConstraints",
            True,
            b"CA:TRUE"),
        crypto.X509Extension(
            b"keyUsage",
            True,
            b"keyCertSign, cRLSign"),
        crypto.X509Extension(
            b"subjectKeyIdentifier",
            False,
            b"hash",
            subject = ca),
        crypto.X509Extension(
            b"crlDistributionPoints",
            False,
            crl_distribution_points.encode("ascii"))
    ])

    subject_alt_name = "email:%s" % email_address
    ca.add_extensions([
        crypto.X509Extension(
            b"subjectAltName",
            False,
            subject_alt_name.encode("ascii"))
    ])

    if ocsp_responder_url:
        raise NotImplementedError()

    """
        ocsp_responder_url = "http://%s/api/ocsp/" % common_name
        authority_info_access = "OCSP;URI:%s" % ocsp_responder_url
        ca.add_extensions([
            crypto.X509Extension(
                b"authorityInfoAccess",
                False,
                authority_info_access.encode("ascii"))
        ])
    """

    click.echo("Signing %s..." % ca.get_subject())

    # openssl x509 -in ca_crt.pem -outform DER | sha256sum
    # openssl x509 -fingerprint -in ca_crt.pem

    ca.sign(key, "sha256")

    os.umask(0o027)
    if not os.path.exists(directory):
        os.makedirs(directory)

    os.umask(0o007)

    for subdir in ("signed", "requests", "revoked"):
        if not os.path.exists(os.path.join(directory, subdir)):
            os.mkdir(os.path.join(directory, subdir))
    with open(ca_crl, "wb") as fh:
        crl = crypto.CRL()
        fh.write(crl.export(ca, key, days=revocation_list_lifetime))
    with open(os.path.join(directory, "serial"), "w") as fh:
        fh.write("1")

    os.umask(0o027)
    with open(ca_crt, "wb") as fh:
        fh.write(crypto.dump_certificate(crypto.FILETYPE_PEM, ca))

    os.umask(0o077)
    with open(ca_key, "wb") as fh:
        fh.write(crypto.dump_privatekey(crypto.FILETYPE_PEM, key))

    certidude_conf = os.path.join("/etc/certidude.conf")
    with open(certidude_conf, "w") as fh:
        fh.write(env.get_template("certidude.conf").render(locals()))

    click.echo()
    click.echo("Use following commands to inspect the newly created files:")
    click.echo()
    click.echo("  openssl crl -inform PEM -text -noout -in %s | less" % ca_crl)
    click.echo("  openssl x509 -text -noout -in %s | less" % ca_crt)
    click.echo("  openssl rsa -check -in %s" % ca_key)
    click.echo("  openssl verify -CAfile %s %s" % (ca_crt, ca_crt))
    click.echo()
    click.echo("Use following to launch privilege isolated signer processes:")
    click.echo()
    click.echo("  certidude spawn")
    click.echo()
    click.echo("Use following command to serve CA read-only:")
    click.echo()
    click.echo("  certidude serve")


@click.command("list", help="List certificates")
@click.option("--verbose", "-v", default=False, is_flag=True, help="Verbose output")
@click.option("--show-key-type", "-k", default=False, is_flag=True, help="Show key type and length")
@click.option("--show-path", "-p", default=False, is_flag=True, help="Show filesystem paths")
@click.option("--show-extensions", "-e", default=False, is_flag=True, help="Show X.509 Certificate Extensions")
@click.option("--hide-requests", "-h", default=False, is_flag=True, help="Hide signing requests")
@click.option("--show-signed", "-s", default=False, is_flag=True, help="Show signed certificates")
@click.option("--show-revoked", "-r", default=False, is_flag=True, help="Show revoked certificates")
def certidude_list(verbose, show_key_type, show_extensions, show_path, show_signed, show_revoked, hide_requests):
    # Statuses:
    #   s - submitted
    #   v - valid
    #   e - expired
    #   y - not valid yet
    #   r - revoked

    from certidude import authority

    from pycountry import countries
    def dump_common(j):

        person = [j for j in (j.given_name, j.surname) if j]
        if person:
            click.echo("Associated person: %s" % " ".join(person) + (" <%s>" % j.email_address if j.email_address else ""))
        elif j.email_address:
            click.echo("Associated e-mail: " + j.email_address)

        bits = [j for j in (
            countries.get(alpha2=j.country_code.upper()).name if
            j.country_code else "",
            j.state_or_county,
            j.city,
            j.organization,
            j.organizational_unit) if j]
        if bits:
            click.echo("Organization: %s" % ", ".join(bits))

        if show_key_type:
            click.echo("Key type: %s-bit %s" % (j.key_length, j.key_type))

        if show_extensions:
            for key, value, data in j.extensions:
                click.echo(("Extension " + key + ":").ljust(50) + " " + value)
        else:
            if j.key_usage:
                click.echo("Key usage: " + j.key_usage)
            if j.fqdn:
                click.echo("Associated hostname: " + j.fqdn)


    if not hide_requests:
        for j in authority.list_requests():

            if not verbose:
                click.echo("s " + j.path + " " + j.identity)
                continue
            click.echo(click.style(j.common_name, fg="blue"))
            click.echo("=" * len(j.common_name))
            click.echo("State: ? " + click.style("submitted", fg="yellow") + " " + naturaltime(j.created) + click.style(", %s" %j.created,  fg="white"))

            dump_common(j)

            # Calculate checksums for cross-checking
            import hashlib
            md5sum = hashlib.md5()
            sha1sum = hashlib.sha1()
            sha256sum = hashlib.sha256()
            with open(j.path, "rb") as fh:
                buf = fh.read()
                md5sum.update(buf)
                sha1sum.update(buf)
                sha256sum.update(buf)
            click.echo("MD5 checksum: %s" % md5sum.hexdigest())
            click.echo("SHA-1 checksum: %s" % sha1sum.hexdigest())
            click.echo("SHA-256 checksum: %s" % sha256sum.hexdigest())

            if show_path:
                click.echo("Details: openssl req -in %s -text -noout" % j.path)
                click.echo("Sign: certidude sign %s" % j.path)
            click.echo()

    if show_signed:
        for j in authority.list_signed():
            if not verbose:
                if j.signed < NOW and j.expires > NOW:
                    click.echo("v " + j.path + " " + j.identity)
                elif NOW > j.expires:
                    click.echo("e " + j.path + " " + j.identity)
                else:
                    click.echo("y " + j.path + " " + j.identity)
                continue

            click.echo(click.style(j.common_name, fg="blue") + " " + click.style(j.serial_number_hex, fg="white"))
            click.echo("="*(len(j.common_name)+60))

            if j.signed < NOW and j.expires > NOW:
                click.echo("Status: \u2713 " + click.style("valid", fg="green") + " " + naturaltime(j.expires) + click.style(", %s" %j.expires,  fg="white"))
            elif NOW > j.expires:
                click.echo("Status: \u2717 " + click.style("expired", fg="red") + " " + naturaltime(j.expires) + click.style(", %s" %j.expires,  fg="white"))
            else:
                click.echo("Status: \u2717 " + click.style("not valid yet", fg="red") + click.style(", %s" %j.expires,  fg="white"))
            dump_common(j)

            if show_path:
                click.echo("Details: openssl x509 -in %s -text -noout" % j.path)
                click.echo("Revoke: certidude revoke %s" % j.path)
            click.echo()

    if show_revoked:
        for j in authority.list_revoked():
            if not verbose:
                click.echo("r " + j.path + " " + j.identity)
                continue
            click.echo(click.style(j.common_name, fg="blue") + " " + click.style(j.serial_number_hex, fg="white"))
            click.echo("="*(len(j.common_name)+60))
            click.echo("Status: \u2717 " + click.style("revoked", fg="red") + " %s%s" % (naturaltime(NOW-j.changed), click.style(", %s" % j.changed, fg="white")))
            dump_common(j)
            if show_path:
                click.echo("Details: openssl x509 -in %s -text -noout" % j.path)
            click.echo()

    click.echo()


@click.command("sign", help="Sign certificates")
@click.argument("common_name")
@click.option("--overwrite", "-o", default=False, is_flag=True, help="Revoke valid certificate with same CN")
@click.option("--lifetime", "-l", help="Lifetime")
def certidude_sign(common_name, overwrite, lifetime):
    from certidude import authority
    request = authority.get_request(common_name)
    if request.signable:
        # Sign via signer process
        cert = authority.sign(request)
    else:
        # Sign directly using private key
        cert = authority.sign2(request, overwrite, True, lifetime)

    click.echo("Signed %s" % cert.identity)
    for key, value, data in cert.extensions:
        click.echo("Added extension %s: %s" % (key, value))
    click.echo()

@click.command("serve", help="Run built-in HTTP server")
@click.option("-u", "--user", default="certidude", help="Run as user")
@click.option("-p", "--port", default=80, help="Listen port")
@click.option("-l", "--listen", default="0.0.0.0", help="Listen address")
@click.option("-s", "--enable-signature", default=False, is_flag=True, help="Allow signing operations with private key of CA")
def certidude_serve(user, port, listen, enable_signature):

    logging.basicConfig(
        filename='/var/log/certidude.log',
        level=logging.DEBUG)

    click.echo("Serving API at %s:%d" % (listen, port))
    import pwd
    from wsgiref.simple_server import make_server, WSGIServer
    from socketserver import ThreadingMixIn
    from certidude.api import certidude_app, StaticResource

    class ThreadingWSGIServer(ThreadingMixIn, WSGIServer):
        pass

    click.echo("Listening on %s:%d" % (listen, port))

    app = certidude_app()

    app.add_sink(StaticResource(os.path.join(os.path.dirname(__file__), "static")))

    httpd = make_server(listen, port, app, ThreadingWSGIServer)

    if user:
        # Load required utils which cannot be imported from chroot
        # TODO: Figure out better approach
        from jinja2.debug import make_traceback as _make_traceback
        "".encode("charmap")

        _, _, uid, gid, gecos, root, shell = pwd.getpwnam(user)
        if uid == 0:
            click.echo("Please specify unprivileged user")
            exit(254)
        click.echo("Switching to user %s (uid=%d, gid=%d)" % (user, uid, gid))
        os.setgid(gid)
        os.setuid(uid)
        os.umask(0o007)
    elif os.getuid() == 0:
        click.echo("Warning: running as root, this is not recommended!")
    httpd.serve_forever()

@click.group("strongswan", help="strongSwan helpers")
def certidude_setup_strongswan(): pass

@click.group("openvpn", help="OpenVPN helpers")
def certidude_setup_openvpn(): pass

@click.group("setup", help="Getting started section")
def certidude_setup(): pass

@click.group()
def entry_point(): pass

certidude_setup_strongswan.add_command(certidude_setup_strongswan_server)
certidude_setup_strongswan.add_command(certidude_setup_strongswan_client)
certidude_setup_strongswan.add_command(certidude_setup_strongswan_networkmanager)
certidude_setup_openvpn.add_command(certidude_setup_openvpn_server)
certidude_setup_openvpn.add_command(certidude_setup_openvpn_client)
certidude_setup.add_command(certidude_setup_authority)
certidude_setup.add_command(certidude_setup_openvpn)
certidude_setup.add_command(certidude_setup_strongswan)
certidude_setup.add_command(certidude_setup_client)
certidude_setup.add_command(certidude_setup_production)
entry_point.add_command(certidude_setup)
entry_point.add_command(certidude_serve)
entry_point.add_command(certidude_spawn)
entry_point.add_command(certidude_sign)
entry_point.add_command(certidude_list)